The present invention relates to an automatic adjusting device for bicycle brakes.
Heretofore, adjusting means to cope with events of the intended braking force being decreased due to wear of the brake shoes and/or elongation of the Bowden cable have been embodied by increasing the pulling force on the inner cable of the Bowden cable or the pushing force on the outer sheath thereof at the end of the Bowden cable on the brake side or brake operation side. The conventional adjusting means, however, are designed to be activated by manual or intentional operation on the adjusting member. Not only is the adjustment thereof very troublesome, but also it is difficult to obtain the proper mount of adjustment. Besides this, it sometimes occurs that the position of the brake operating lever is changed after adjustment, thereby adversely affecting the rider's attitude when he grips it. When the traction force on the inner cable of the Bowden cable is to be increased, as an example, by the adjusting means, it is necessary to pull the inner cable with a corresponding high strength. In the case of a brake consisting of a combination of large and small arches as in a side pull type caliper brake, however, since these arches are maintained in their opened or expanded condition by means of a spring, the large and small arches must be contracted against the force of the spring at the time of adjustment. It is, therefore, almost impossible to strongly pull the inner cable. This is the present situation, which is very serious from the standpoint of safety.